Third Grade ◆ Lesson One
Mass creates form, which occupies space and brings into being a spatial articulation.
Social structure, culture and the built environment have a direct influence on one another.
Drawings comparing English and metric lengths of some common objects (included).
The English and metric ruler (included). Photocopy to the exact size shown and cut out for each student.
VOCABuLARy (See glossary for definitions)
The teacher gives students a brief history of the metric system by explaining the following:
The metric system began in the 1200s in England as a method for measuring length, volume, temperature, time, and weight or mass.
Most countries other than the U.S. use the metric system today; the U.S. uses a system called the “customary” or “ English” system.
Early in the 1970s, Canada began to convert from the “customary” or “English” system to the metric system.
In 1975, the U.S. Congress passed the Metric Conversion Act, calling for a voluntary change over to a system of metric measurement.
The metric system is based on units of “ten” and is simple to use.